Versatility and mobility in medical devices, particularly in medical devices to be used internally of a patient, are important, and can be especially important in minimally invasive surgical procedures. Minimally invasive surgical procedures are typically conducted through small ports, in contrast to the larger incisions typical of open surgery. Such procedures are called by a variety of adjectives, including endoscopic, laparoscopic, thoracoscopic, and the like. Endoscopic surgery will be used herein to describe these procedures.
Typical state of the art endoscopic procedures demand new families of instruments, and a variety of custom-designed instruments have been created for such procedures. Their common feature has been the ability to be passed through the cannula of a trocar, or other small opening (typically less than 1 cm. diameter) into the body, or through a natural orifice of the body. In contrast to the instruments of classical surgery, this requires a narrow diameter, and often the ability to manipulate the distal end of the device (the end within the body) from the proximal end (the end outside the body). Because endoscopic surgical procedures were initially perceived as extremely demanding, instruments were and are carefully optimized for each individual procedure. This custom optimization makes endoscopic instruments inherently expensive.
As the number of endoscopic procedures increases, there is a need to simplify the process of creation of suitable instruments, and to make their manufacture more efficient. This is especially important in the treatment of medical conditions with relatively small incidence, for example, those in which the annual incidence is a few thousands or tens of thousands.
In addition to endoscopic use, there is a similar need for specialized devices for various forms of open surgery which can be engineered and manufactured in an economical manner.
In many of these areas of surgery, there is an increasing use of structure-forming fluids, which may require custom variations in the design of the applicator. Examples of such custom uses include the local application of hydrogels, hydrogel precursors, and other structure-forming materials to form sealants, adhesives, pavings, barriers, tissue supports, tissue engineering substrates, and drug delivery depots.
Many medical devices with removable and interchangeable components are known. U.S. Pat. No. 5,507,772 (Shunt, et al.) discloses a surgical instrument including a removable tip assembly having an elongated support member including a proximal end configured to be coupled to a handle and a distal end for insertion into a patient's body. The surgical instrument includes a handle having a body portion formed to include an opening for receiving the proximal end of the tip and a locking mechanism for removably coupling the selected tip assembly to the handle.
U.S. Pat. No. 5,752,972 (Hoogeboom) discloses a modular surgical instrument which includes a handle, an end effector, and an elongate tubular sleeve extending between and opposing the end effector and the handle, a reciprocating actuator rod disposed within the sleeve. The disclosed arrangement allows an end effector to be easily removed from the handle and replaced with a different end effector, thus reducing costs associated with replacing one end effector and eliminating the need for providing each end effector with its own handle.
U.S. Pat. No. 5,766,157 (Tilton, Jr.) discloses a method and apparatus for laparoscopic insertion and application of a liquid, gel or like medicinal material that enables the laparoscopic surgeon to utilize various spray patterns to apply the desired material. The instrument consists of an elongated instrument body that can receive a selected flexible delivery tube having a distal end with a nozzle. The selected nozzle of the selected dispensing tube can be flexed to dispense with a desired spray pattern into any position of the patient's abdominal cavity.
U.S. Pat. No. 5,807,338 (Smith, et al.) discloses a modular trocar system which includes an obturator assembly, and a cannula assembly. A method of assembly is also provided and includes the steps of connecting a shield member, attaching a knife blade, and attaching a first housing section to a second housing section with a quick connect mechanism which includes first and second mating portions such that the first and second housing sections are movable from a spaced apart position to a connected position in a single motion.
U.S. Pat. No. 5,868,767 (Farley, et al.) discloses an intravascular universal catheter having interchangeable work elements and methods of use. Preferably, a lumen is configured to allow the work element to be completely withdrawn from the catheter body, so as to permit interchange of various work elements.
U.S. Pat. No. 5,876,344 (Baker, et al.) discloses a catheter assembly and method in which an imaging transducer is positioned proximally of a treatment device at the distal end of a catheter. The catheter, the treatment device, and the transducer are all constructed as individual modular units which can be assembled together as desired to form the assembly.
International Application WO 98/22175 (Sachdeva, et al.) discloses a modular balloon catheter with proximal and distal shaft which can be coupled by a connector made from a shape memory alloy. The proximal shaft of the catheter can be connected to the fluid supply source by either a conventional connector or a connector which is designed for and is made of a shape memory material.
While the above and other documents describe a variety of useful medical devices, modern demands for economy and speed have created a need for a better way of designing and making custom applicators. It is an object of the present invention to provide improved medical devices, especially for application of agents to body surfaces.